A design method to assess the primary strength of the delta-type vlfs

Roy Gafter, Nitai Drimer

Research output: Contribution to journalArticlepeer-review


Very large floating structure (VLFS) is a sustainable concept centered around creating solid platforms at sea. The Delta is a new type of VLFS, designed to withstand open-sea conditions and to form, in addition to a broad deck areas, a sheltered basin of year-round operability. The design of this unique hull relies on direct calculations in order to identify critical load cases and assess their load effects. This study formulates a theoretical procedure for the initial assessment of the primary strength. The procedure analytically integrates the floatation loads while the hull rests at hydrostatic equilibrium on a wave surface and obtains the vertical and horizontal bending moment. This preliminary assessment tool enables a fast review of many load cases and provides the basic insights necessary for a reasonable initial design. Using the procedure, we conducted a primary load assessment for the design of Delta. By calculating the load response to 588 load cases, we identified the critical load scenario and the maximal axial stress. As the stress was too high, we improved the geometry in order to reduce loads and assessed proper scantlings for the critical section. We present the formulation of the procedure, the validation of the results, and the implementation for the structural design of the Delta VLFS.

Original languageEnglish
Article number1026
JournalJournal of Marine Science and Engineering
Issue number9
StatePublished - Sep 2021


  • Hull girder
  • Primary strength
  • Structural analysis
  • VLFS

All Science Journal Classification (ASJC) codes

  • Civil and Structural Engineering
  • Water Science and Technology
  • Ocean Engineering


Dive into the research topics of 'A design method to assess the primary strength of the delta-type vlfs'. Together they form a unique fingerprint.

Cite this